infectious disease
tsmith | November 16, 2006 I was just lecturing yesterday on streptococci, and discussing how the diseases caused by the group A streptococcus (Streptococcus pyogenes). This is the bacterium that causes diseases as varied as "strep throat," streptococcal toxic shock syndrome, and necrotizing fasciitis (aka the "flesh-eating disease.") It's also caused historical epidemics of scarlet fever, a major scourge in many countries from the mid-1800s or so until around the turn of the century, when it started to wane for no apparent reason. (The worry over this illness was captured in Margery Williams' 1923 book, "The…
revere | November 16, 2006I will admit to admiring the people of Cuba and having respect for what their health care system has done for them against great odds and in the face of a vicious US embargo. I've seen it with my own eyes, and although things have fallen on hard times because of the embargo, it performs better than anyone would have a right to expect. It is true Cuba's government is not a model of tolerance and can be very repressive, a tendency aided and abetted by US policy. But the spirit of the Cuban Revolution still has my admiration. They aren't worse, and in fact are better than many staunch US allies…
tsmith | November 10, 2006Scienceblogs' coturnix is hosting this month's edition of Carnival of Pozitivities, collecting posts on HIV/AIDS from around the blogosphere. Check it out for a number of excellent posts, including this post on HIV, senior citizens, and how politics affects HIV education.
tsmith | November 8, 2006Sometimes, I'm really, really glad that I didn't go into medicine. Via Pediatric Grand Rounds and Flea comes this story of a baby's death from herpes encephalitis. I mentioned previously that, while I work with pathogens that have been isolated from someone who had a serious infection, or even died, it's easy to just think of them as bacteria, rather than the cause of someone's death. Just studying their evolution and pathogenicity is interesting unto itself, but sometimes we need to be reminded again *why* we're studying these--and this story again is one of those reminders.
tsmith | November 7, 2006Male circumcision is a difficult topic to discuss rationally. At the core, it's a medical procedure, but it's one tinged with centuries of cultural influences, and emotions tend to run high on both the pro- or anti-circumcision side of the discussion. One of the reasons that's been given in favor of circumcision is that it lowers the risk of disease, including diseases transmitted by sexual contact. However, while this data has been fairy unambiguous regarding some diseases (including the reduction in HIV transmission due to circumcision), the effect circumcision has on the spread of…
tsmith | November 2, 2006Apparently, it's just not enough for this administration to push ineffective and inaccurate abstinence-only education programs for our schoolchildren. Nope--they're also being emphasized for adults up to the age of 29, as well:
If you're single and in your 20s, the federal government wants you to steer clear of sex.
That's the new guidance for states under the Department of Health and Human Services' $50 million Abstinence Education Program. HHS officials say it's not a requirement -- just another option for states to combat what they call an alarming rise in out-of-wedlock births.
(More…
revere | October 26, 2006When it comes to vaccinations, a high degree of safety is one of the paramount issues. This is because even a small risk, like one in a million, when multiplied by tens of millions will produce tens or more of adverse events. The trade-off, of course, is the prevention of the disease the vaccine is directed against. Unlike a therapeutic drug, when a vaccine works, nothing happens. When there is a side effect, a previously well person becomes sick from the vaccine itself. This becomes a tricky problem in public health education. The recent scare in Israel with influenza vaccine illustrates…
revere | October 24, 2006We're getting down to it. What's the scientific basis for a lot of advice that's being given out as if its uncontroversial. Like washing hands. Or shaking hands is the way flu viruses are passed around. From Helen Branswell's usual superior reporting:
Might we all be a little healthier this cold-and-flu season if we abandoned the handshake culture? With mounting concern about a possible influenza pandemic and growing awareness of the economic costs respiratory ailments exact through absenteeism, some people are wondering precisely that. (Branswell, Canadian Press)
Makes a lot of sense.
Those…
tsmith | October 24, 2006Orac has an excellent post discussing the rise in pertussis ("whooping cough") in many areas, and its correlation with easier exemption from mandatory vaccination (using a "personal belief" exemption in addition to a religious exemption, for example). I've written about pertussis previously, and a problem is that the vaccine effectiveness quickly wanes, so that adults frequently lack significant immunity. While we rarely get sick, we can be carriers of the bacterium and infect children around us. As such, new recommendations suggest that adults also should get a pertussis booster. I worry…
tsmith | October 24, 2006 Regular readers know an interest of mine are infections that cause more than just the typical acute spectrum of disease. For example, I've written on the role microbes might play in obesity, or the role of viruses in chronic disease such as cancer and, of course, AIDS. Still, typically, infections are thought of as acute and self-limited; that is, they infect the individual, cause illness, and are resolved in a matter of days or weeks, even though we know that this doesn't always happen. And increasingly, we're finding that infections are associated with all kinds of long-term diseases…
tsmith | October 23, 2006Apologies for the radio silence, so to speak. October has been a killer month for me and November won't be that much better, but I'll work on getting back to posting on a regular basis, including a new post for tomorrow. In the meantime, a few things to check out:
Mike on treating strep throat (which he's correct is near and dear to my heart--though not literally, thankfully, since they can cause heart disease!).
A belated Friday the 13th Tangled Bank
Last week's Grand Rounds.
revere | October 23, 2006It's an influenza vaccination program's worst nightmare. In Israel, four elderly and chronically ill patients have died of cardiac arrest within days of receiving influenza vaccinations:
Israel suspended flu vaccinations nationwide on Sunday after four men who had been inoculated died in the past week, the Health Ministry said.
"I ordered to stop the vaccinations until things are made clear," Israeli Health Minister Yacov Ben Yizri told reporters.
"We have started to investigate everything related to this case," he said. The ministry said it had asked the French firm Sanofi-Aventis, which…
tsmith | October 13, 2006Flu shots are rolling out, and there should be no shortage this year. A few new articles remind the public of the importance of these vaccinations, especially in high-risk groups (something that I touched on here regarding data showing that vaccination during pregnancy can help protect the newborn).
You can find the guidelines for target vaccination groups here. Essentially, it includes anyone immunocompromised or with conditions that make them increasingly susceptible to serious complications of influenza; those 50 years of age and older; and children from 6 months to five years old.…
tsmith | October 6, 2006Toddler's death blamed on E. coli, officials say
Heartbreaking.
As federal agents launched a criminal investigation into two produce companies involved in the contaminated spinach outbreak, Idaho health officials confirmed the death of a 2-year-old boy Sept. 20 was caused by tainted spinach.
Kyle Allgood was the second confirmed death in the E. coli outbreak, which also killed a Wisconsin woman.
The boy, who would have turned 3 in December, died in Salt Lake City after developing a type of kidney failure caused by E. coli. Health officials had to wait for the results of genetic testing on the…
tsmith | October 3, 2006I write on a somewhat regular basis on here about vaccines: new research, new shots, addressing skepticism about how well they work or if they're related to autism, etc. Recently, several vaccine stories have been in the news that I've not gotten to yet, so consider this a vaccine meta-post. More after the jump.
The first story is timely in that it discusses the influenza vaccination (and we're heading into that season). Allow me to share an anecdote first. When I was pregnant with my daughter in 1999, I was in graduate school and the lab I worked in was affiliated with a hospital. So…
tsmith | October 3, 2006Orac has a post up on this new JAMA paper as well. He brings up some better examples than the one I gave:
Does anyone in this day and age still believe that smoking doesn't cause lung cancer? The epidemiological evidence of the association is bulletproof. However, the majority of smokers don't get lung cancer. In fact, there are complex statistical models that allow a pretty accurate calculation of risk in populations based on how long and how much a smoker has been smoking. For example, if you start smoking at age 18 and smoke two packs a day, by age 55, you have about a 5% chance of dying…
tsmith | October 2, 2006Ah, another day, another paper for the anti-HIV establishment to glom onto and misrepresent.
Last week's issue of the Journal of the American Medical Association published this paper examining the relationship between HIV load and CD4 T-cell decline:
Context Plasma human immunodeficiency virus (HIV) RNA level predicts HIV disease progression, but the extent to which it explains the variability in rate of CD4 cell depletion is poorly characterized.
Main Outcome Measures The extent to which presenting plasma HIV RNA level could explain the rate of model-derived yearly CD4 cell loss, as…
tsmith | September 29, 2006Nina Plank, the author of the NY Times article I commented on in this post, stopped by to comment. Rather than just having this lost in the comments to a week-old post, I wanted to take a moment and quickly address two of her points (with potentially a follow-up post next week when I have a bit more free time).
First, to Nina, thanks for stopping by. I'll just say that I very much disagree with your stance on raw milk and dairy. Indeed, contamination can also happen after pasteurization and nothing replaces vigilance, but having seemingly healthy cows is no guarantee of healthy milk.…
tsmith | September 26, 2006I was travelling over the weekend and I'm incredibly busy up through Wednesday, so new material from me will have to wait until later in the week. In the meantime, I'll point you to a stellar post I wanted to highlight last week, from Revere on H5N1 and the evolution ov virulence, and another excellent one from Mike regarding the importance of surveillance when it comes to detecting and containing outbreaks (such as the recent O157 outbreak). He also describes a timeline for how long many of the common procedures take; quite a bit different from what you get watching CSI or similar shows…
tsmith | September 21, 2006 That's certainly the claim in a new New York Times editorial (via The Frontal Cortex). The author, Nina Planck (author of Real Foods: What to Eat and Why), claims that it's as easy as just feeding cattle grass, and poof!--E. coli O157 will vanish.
More on this and why organic farming won't necessarily stop such outbreaks after the jump.
Planck writes:
Where does this particularly virulent strain come from? It's not found in the intestinal tracts of cattle raised on their natural diet of grass, hay and other fibrous forage. No, O157 thrives in a new -- that is, recent in the history of…